


An Open Expirment

by RandomJaz



Category: Invader Zim
Genre: F/M, M/M, Multi
Language: English
Status: In-Progress
Published: 2016-04-14
Updated: 2018-05-27
Packaged: 2018-06-02 07:35:03
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 7
Words: 19,683
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6557533
Author URL: https://archiveofourown.org/users/RandomJaz/pseuds/RandomJaz
Summary: <blockquote class="userstuff">
              <p>Gaz takes an interest in her older brother's xenophelia, going as far as to step in herself and partake in it. Her interest in her brother and his extra terrestrial press the boundaries of their relationship as well as the once controlled environment he set in place for his study of the alien's anatomy and physiology.</p>
            </blockquote>





	1. Chapter 1

AUTHOR'S NOTE: I started this story experimentally, so this chapter is super short. If you like it just let me know and I'll continue :) Thank you for reading!

I never thought I'd see the day Gaz showed me any interest.

She stood in the doorway of my bedroom, eyes locked on to mine. Her impassive face unimpressed per usual. Her mouth was drawn in a line, teeth probably touching inside her mouth. She looked like that whenever she walked in on me, but unlike her normal routine instead of walking away with some monotone remark, she stayed.

My glasses were off, placed somewhere on my desk. Zim lay on his stomach, his ass in the air as my dick was buried so deeply in to him his cheeks squished under the weight of my pelvis. He was panting hard, having been fucked in to the mattress a few seconds ago. My tall lanky body outsized him fairly. The creak of my door caught both of our attentions as we rattled the bed springs and I stopped to see who had entered my room.

It wasn't the first time she forgot to knock, she'd walked in on us before. The recurring event struck me as oddly repetitive and I wondered if maybe she actually hadn't forgotten to knock. It seemed as if she purposely skipped it. She'd walked in so many times, headphones in ears and videogame in hand, that it was almost normal.

She would normally say whatever she had to tell me, usually that she needed a ride. Or that Dad would be gone for another couple of days and our allowances and grocery money were already wired to our bank accounts. But this time she said nothing, standing there with her headphones and game console missing. Her brown eyes were unconcerned, blinking normally with steady slips of her eyelids. They were focused on us.

Her eyes were always uninterested, matching her cold temperament. I was used to it, oh boy was I used to it. She often ignored me unless it was otherwise convenient for her. But she really surprised me this time, standing there as if there was something interesting to see. She still had on her beat up converse sneakers, and her eyeliner was smudged under the lower lids of her eye. Her purple lipstick was worn off in the center of her lips, probably from whatever she'd eaten at lunch.

She'd gotten home from school probably minutes earlier and I realized it was much too early for her to be home. The highschool let out at two, there was no way it was two. Zim came over as soon as she left for school, he'd only been here a few hours. It had to be twelve o' clock at best.

"Why are you home?"

"Early release" she responded, unmoving from the door frame. "Thought you had class."

"It's Tuesday"

Gaz Knew my schedule. Monday, Wednesday and Friday I was at the community college all morning, then I'd come home. Usually with Zim. She wasn't the type to forget things. She knew I was home. If not from the shere fact it was Tuesday, Zim's erotic screaming carried through the door of my room when we were alone.

"Oh" Her answer was lazy, almost like she said it as an afterthought. Like she hadn't planned on replying at all.

Zim's green skin darkened around the swollen slopes of his ass and face and he groaned, a very very low keening sound. His large ruby eyes were looking at the foot of my bed and I kept my eyes to the right, watching my sister. At this point my nudity didn't phase her, or the position I was in. She flicked her eyes down to Zim, noting his distressed noise.

"What's wrong with him? He looks like he's in pain."

"He's in heat" I answered her simply.

She blinked once, looking at Zim as he groaned underneath me. He didn't care that he was being looked at, he didn't care in the least. He just wanted me to relieve him of the discomfort he felt, the insufferable heat in his loins. Gaz being there didn't effect him, he just didn't like that her presence stopped what I had been doing to him.

"You trying to knock him up or something?" Her question was so casual, voice only slightly less raspy than years before.

"Of course not."

I inched back out of Zim just a bit to show her the rubber strapped on to me but thought better of it and stopped. I didn't need to show her, I didn't need to tell her. She walked in on me unannounced, I could just throw her out and have every reason to do it. I didn't though.

"You should wear a condom then" she suggested bluntly, shrugging like she'd told me something as simple as what she wanted for dinner. "He can get pregnant, or at least that what your log said"

I ignored the fact that she'd gone through my studies, reading my reports on Zim. I didn't care in the least. She did as she pleased when she pleased, always going through my experiment findings and reading up on whatever I'd discovered about the alien beneath me.

"Did you need something?" I asked her finally, confused about her extended stay which was dragging on. By now she would have been long gone. "I'm in the middle of something"

"I can see that"

And there it was again, the look in her eye. The subtle intrigue of what she took in before her. I gave her a questioning look, unsure of what she was up to. She stared at me and she leaned off the doorway a little, and I anticipated the click of my door shutting as I leaned back up from my knees to carry on with Zim.

I froze as I heard her shoes scuffing the carpet in my room, followed by the click of her closing the door. Turning back to her I was faced with her apathetic face, expression emotionless but she looked at me expectantly. It was now obvious what was going on, and I didn't know where to begin on how to feel about it.

"What are you doing?" I acted dumb anyways.

She shrugged, her shoulders coming up to brush the large flips of her shoulder length hair. It bounced, the strands shifting stiffly with whatever sticky hair product she had in it. I didn't question her further and she walked past my bed and sat down at my desk chair, the piece of furniture turned to face Zim and I.

"Just observing" she told us, crossing one leg over the other. Striped knee high socks leading up to a purple skater skirt and a black long sleeved shirt.

"This isn't an observation study"

Gaz tapped her foot. Still watching us.

Zim's long skinny fingers scratched at the bed sheets and he pushed back against me, the low keening sound coming from deep in his throat. The muscles where we connected constricted on my still prominent erection, begging for stimulation.

"We're waiting."


	2. Chapter 2

AUTHOR'S NOTE: Thank you so much to my guest reviewer on the fanfic site! I'm so glad you reviewed, and even happier that you enjoy this story :) I appreciate the feedback more than you understand.

Thanks for reading guys! Please let me know your thoughts with a review or comment. I've got the next chapter planned and I'll get started after I hear some thoughts.

"We're waiting"

Gaz looked at me patiently, almost too patiently. I knew my sister and she was never quite that understanding. She was waiting for me for me to carry on, expecting me to. It wasn't a matter of her testing the waters. She was only patient because she completely anticipated that I would keep going and leave her to do as she pleased.

With Zim's desperate clawing under me and my sister's puncturing eyes looking at mine I couldn't ground myself enough to argue with her, even though I should have. It wasn't normal for your younger sibling to sit in on your sexual activities. Especially ones that hate you and have from day one. I gave her one last questioning look, hoping she'd understand what she was doing and think better of it and leave.

She blinked.

I shifted on my knees again, still inside Zim, and the alien groaned as I brushed something inside him without meaning to. Unlike humans, he didn't sweat through his skin. His heat stayed inside him, building until he could cool his body off by some other means. The anatomical defect was horrible, making his sexual heat so so much more difficult for him.

"Gib-human!" He grunted at me, sounding needy and ungratified in every sense possible. "I burn! This heat, it burns me from inside..."

He placed his flush cheek down on the bed and girated his backside in to me, not having the energy to really fight for what he wanted. Gaz looked at him and back to me, quietly guilting me for leaving him in such ruins. She didn't really care at all and I knew it. She was prodding.

It didn't stop me from taking Zim's hips in my hands and thrusting. He wailed so loudly that had Gaz actually left us to do as we would, like a normal person, I would have slapped my hand over Zim's mouth. He never sounded quite like THAT. He wailed and keened lowly, letting me move how I pleased inside him. A gland inside him secreted a translucent, lightly purple but almost clear lubricant, which was still coming out as I fucked him.

His body fascinated me. As a kid I couldn't understand how his human disguise even passed as believable being I was so obsessed with outing his existence as an alien. Once getting over that and choosing to study him privately, with his mutual consent, I could see how similar to a human he really was in terms of phenotype characteristics.

His body was built like humans, with arms longer than his torso and legs that were longer his arms. His head was slightly larger in proportion to his body but his relatively longer neck helped to add illusion that it was merely an enlarged feature. Such as a broad forehead underneath the black wig he wore, not that others knew it was wig.

He had shoulders that connected to a stout back which tapered down to two hips. And below his hips were two cheeks, just like any human. He was green which wasn't the easiest to look past, but he looked pretty anthropic. Contacts were worn outside and covered his very bright red eyes, and besides the phallic organ he did have and lack of nose, he was not very different than a normal man.

He had two sexual organs, oddly enough. My studies confirmed that his phallic organ which looked very similar to a human penis, just lacking external testicles and a circumcised appearance, did in fact work just as a humans would. Furthermore my studies concluded he also had a set of reproductive organs inside him. A receptive pouch for his waiting to be fertilized eggs which connected to his anal canal, and a seminal gland for the impregnation of others. Though having hermaphrodite-like anatomy, he could not impregnate himself.

Zim's heat was so much more chronic after he'd undergone a hormonal treatment I administered to him experimentally. He wanted to be taller, and he now was, but something changed inside him. His sperm were weak but his body pumped egg bearing hormones through him as if he were strictly female. His hormones were far more unregulated than they had been prior to the experiment, making the alien no better than a wanton whore when in heat. He couldn't go without the relief, he'd go crazy.

Even as I rocked him up and down in to the mattress springs he was besides himself with desire. His body craved seed, but I wouldn't give it him. The orgasms consoled his biology for only so long, his body seeking a taste of a fertile male's gametes. The condom on my dick was Zim's ruining, he knew that. But he didn't care for any offspring, neither did I.

"Why does it sound like you're hurting him?" She asked in such a way that would imply she wasn't sitting in on something she shouldn't be, like it was perfectly fine to talk to me while I fucked him. "His face is red."

"I'm not hurting him" I didn't want to explain any further being I was balls deep in him, trying to please both our arousals. The audience being a distraction on my part.

"It looks like you are." The observation wasn't sympathetic, it was just an observation.

To prove what I tried telling her, I hooked my arm under Zim's stomach and pulled him up to press his back against my chest. His beating erection throbbed dramatically. The shiny surface of his phallus jutted out from his pelvis, showing how pleased he really was.

I gave my sister a validating look, hoping she'd shut up about it now. Her eyes weren't on me though at that second, they were on Zim's waist. She watched his erection bob with the back and forth bouncing from me impaling him. She looked up when he made another gluterral moan, nearing his finish. And when that happened, I needed to pull out at all costs.

"Why don't you touch him?"

"He doesn't always like that"

Sometimes Zim was so desperate for his release that he'd let me touch him or he'd touch himself. But being his phallus was not the primary functioning sexual organ of his body anymore, he didn't always like it stimulated. Sometimes it just made things worse by confusing his already confused body, a result of his endocrine system being scientifically tinkered with.

"Try"

My hand reached for Zim's phallus and he hissed, lurching his pelvis away from my hand and slamming it back in to me. I took my hand back, making a mental note of the unusually aggressive reaction. He never hissed at me before. That was new.

His body shook and he looked right at Gaz, a clicking sound coming from his throat. She didn't look scared at all, if anything she looked kind of...satisfied? Smug almost. Her mouth curled slightly at one side, her eyes squinting just enough that I could see she was up to something. Zim was acting different. His antenna pulled back, the tips beating lightly on his skull.

He started moving faster against me, matching my thrusts with movements of his own. He reached behind him, gripping my side with long, skinny fingers and held me like I was trying to pulling away. Which I wasn't.

"Give me your seed"

It was a demand he'd never given before. His voice was altered, the sound of it peaking notches higher in pitch as he began slamming himself back in to me. He kept watching my sister, straightening his body out as if he were protecting me from her. It baffled me as I kept on, his now seemingly possessive behavior.

I looked back to Gaz, wanting to see her reaction to his strange behavior. I thought she would be scared. She looked right at me, smiled naughtyly, and took her breasts in hand through her shirt. Zim trembled in my arms and I couldn't tear my eyes off her as she dipped one hand up under her collar to flash a glimpse of her cleavage at me. Before she could bring the collar of her shirt low enough to show me the material of her bra, Zim suddenly snapped forward like he was going to leap at her while he was on the brink of cumming.

"His seed is mine!"

I tore my eyes off Gaz and held zim to me tightly, fucking him hard a he tried pulling away with vicious sounds aimed at my sister. The sounds became choked as I pushed him towards orgasm, knowing it was a sure fire way to sedate him. Harder and harder I rammed in to him, making him drool. It oozed from his mouth, dripping from his chin as he watched Gaz as he came.

I pushed him off me on to the mattress below as I felt his entrance begin to close in with the vice like grip I found out about our very first time around. My erection out of him, his anal passage puckered shut to contain the semen that would be there if I had not been wearing protection...or if I even came.

I breathed very heavily, the laboredness of it a mixture of unsatisfied arousal and adrenaline from the situation that just transpired. I looked down at Zim not knowing what his problem was..or had been. I wiped my forehead of the sweat collecting there, scrunching my face perplexed as he now laid there placidly. He'd been ready to attack Gaz moments earlier.

"What the fuck?" I sighed, out of breath. " .Fuck."

"Why'd you pull out of him like that? It doesn't look like you finished"

Gaz really had no perception of how overstepping she was being sitting in on us... I'd be lying if I really believed that.

"H-He closes down when he...finishes. Makes penetration i-impossible."

"Well I guess he won't be blowing you instead " She deadpanned, having seen the inside of Zim's mouth on many occasions. "Not with his teeth."

It was true, Zim's teeth were far more pointed than human teeth. I offered filing them down for camouflage purposes but that was one thing he would not allow me to do. He didn't want anything else about his appearance permanently changed in any way, something about one day returning home. They'd respect him he said, now that he was taller.

"You're right" I admitted to Gaz, rubbing my face with frustration. From both Zim's behavior and my pulsing erection." Fucking Christ..."

"So he closes up, huh?"

"Yeah...bring me my glasses, would ya?"

She got up from my desk chair, plucking my prescription eyewear off my desktop and walked over to the bed. She stood by the side of the mattress, looking over my shoulder at Zim who was laying on the bed flat like when she'd walked in. She looked at his ass, cocking her head to the side just a little.

"How does he close up, anyways?"

I split his cheeks apart, showing her the tightly puckered orifice. It closed in so tightly in on itself that it looked almost spiraled. I poked it with my finger to show her just how tight it was and she hummed flatly. She looked at my erection, not commenting. The condom was coated in Zim's lubricant, making the latex shimmery

"Glasses, Gaz" I requested, taking my hands back from Zim's backside and waiting for my sister to hold them out to me. "It's just his lubricant."

She didn't move at all. I craned my neck to look at her and she held my glasses with both hands, playing with the arms. She folded them and unfolded them up and down a few times. I tried taking them and she held them away, holding them behind her back. It wasn't an emergency, I wasn't so blind I relied on them to see but I still wanted them back. Zim needed to be looked at.

"What are you gonna do about it?" Gaz asked cooly, glasses still behind her back.

"Please just give me my glasses, Gaz. "

"That's not what I'm talking about"

The look on my face probably conveyed my confusion and she tipped her face down towards my crotch. I paused, not knowing how to answer her. Zim began rousing and he sat up, back to his calmer normal self. He was a little lethargic from the sex and sat at the foot of the bed, legs crisscrossed as he looked at us.

He looked at Gaz and from her previous reaction to her I thought maybe he would lash out or even look unhappy but he was fine. His normal, post coital, sedated self. I watched him for any other weird behaviors to log later on but he didn't show any. Totally normal.

Something wasn't adding up.

I left the thought alone as Gaz's hand rested on my shoulder, becoming heavier as she pressed her body weight on to it. The scuff of her shoes being slipped off registered in my ears and I wondered what the hell she was getting comfortable for. As she took her hand off my shoulder I was going to ask her but I heard two tissues being pulled from the box on my bedside table.

They were placed in my line of view and I took them, thanking her under my breath. I gripped the end of the condom, pulling the lip of it up with the tissue. A string of sticky precum was stuck to it, connecting the tip of my penis to the condom. After balling up the condom with the tissue I twisted to the side to pitch them in the small trash pail on the floor.

My glasses were still in Gaz's hand, now held in her loose fist on top of her thigh as her arms hund straight down. I tried taking them from her again but she held them away, putting them behind her again, no explanation.

"Gaz"

"So what are you going to do about it?" She questioned, targeted on an answer. "You didn't answer me."

I still didn't answer her. The silence that took over was way more uncomfortable than her sitting in on Zim and I. Even more uncomfortable than her openly looking at my dick while standing right by me. She stared at me for a few more seconds then took my glasses and put them on my nightstand.

She immediately stepped in front of it to block me from taking them but I didn't even try to, still trying to figure out what she was up to. In the back of my mind I had a feeling where she was going, the image of her tugging down her shirt being a nagging feeling in my gut.

She pulled her shirt off, letting it fall to the carpeted floor. Her bra was grey with skulls on them, surely something she'd gotten from punk culture store by the videogame shop. I couldn't talk as she let her skirt slip to the rug, revealing that her underwear did match. Her knee high socks were black and white, striped all the way to her knees.

I still couldn't make any sound as an amaturely manicured hand reached for me, her nail polish black and chipped. Her nails were short and accented by a bead bracelet she had on her ghastly pale wrist, the beads matching her choice of polish.

When her fingers were close enough to touch me I grabbed her wrist, stopping it immediately. The fog in my mind cleared away and I looked at her in disbelief. And of course she looked as unimpressed as ever. She even scowled.

"I'm trying to help you" she sounded irritated with me, such familiarity.

"You don't to 'help."

I didn't need to tell her that, she never did nothing she didn't want to. Her fingers curled in to her palm as I held her wrist, nervous to let go.

"If you want to help, put your clothes on and go to your room"

Zim was looking in on us, blinking his large ruby eyes with mild curiosity. Gaz gave him a side glance with a slow shift of her eyes before settling them back on me. It was beyond unsettling how calm she was, like I was the one being difficult. Like I was the one crossing a boundary.

"Maybe I need help too." She almost made me sound selfish.

It sunk in what she was implying and it left me floored, regardless of already have suspecting what her intentions were. At that point she just helped herself, and straddled me. She swung one leg over my lap and pulled the other one up off the floor and on to the bed. Resting back on her ankles, she arched her chest forwards towards me.

She reached behind herself and undid the clasp to her bra. The cups sagged a bit as the material dropped down from the lack of tension in the strap. She let it slide down her arms before tossing it over her shoulder where it landed on Zim who looked at it with confusion. He didn't know what it was.

Her breasts were fairly small, soft protrusions on her otherwise flat chest. Her nipples were pierced and I couldn't figure out how she'd managed to get it done being she was only seventeen. I looked at the jewelry in sincere surprise and she lightly tugged on the end of one.

"Tyler" she explained to me, and I silently vowed to never drive her to his house again.

The pierced nipples were then right in front of my face as she raised herself up to slip her underwear down one leg and then down and under the other. She slid herself down on to me and I met no resistance when inside her, just wet slippery walls. Again, I vowed to never drive her to Tyler's.

She took control, moving herself on me how she liked. She could hear me groaning, lost in the feeling of her bare, human flesh. It didn't seem to phase her though as she grinded down on my hips. I'd never felt a woman before, or any human for that matter. Gaz was so much softer inside than Zim was.

The green alien himself was looking at us. He observed us, knowing we were partaking in the same thing he and I had done previously. He didn't look jealous, or violent. He watched us, honestly curious. When fingers held my shoulders extremely tightly, I was hit with the reality that my sister was the one on top of me.

It was hard to snap myself out of it, to push her off me. I was too far gone in what was happening. As she sped up on top of me I put my palms on the sheets below to keep myself upright, using my backwards outstretched arms for leverage. My body and mind were torn.

Gaz didn't moan but her breathing was ragged, outing her will to stay as quiet as possible. She didn't like showing emotion, especially not to me. My seventeen year old sister was riding my dick and all I could think about was how quiet she still was...until a particularly wet sounding squelch of her flesh on me reminded me of the lack of protection.

"G-Gaz, I'm not wearing anything." I gasped, feeling her inner walls squeezing me. "If I cum-"

"If you cum, nothing." She didn't even stop to tell me, too busy working herself towards orgasm. " I'm really close, move"

I lifted my hips to meet her and as I bucked up she moaned, then slapped a hand over her mouth. She refused to look at me when it happened and I saw an opportunity. Taking her free hand in mine, I used my other to snatch the one on her mouth. I let myself fall back on to the bed, gripping her hands in mine as she tried taking them back.

"Let go of me!"

"You want to explain what's going on here?" I offered as an escape route, curious to her random interest she took in me. Wanting to know why she was doing this.

"Shut up"

Gaz wasn't weak, she was fairly strong for her size. Keeping her hands confined was more difficult than I assumed it would be and she almost freed herself as she tugged them back when I wasn't ready. I tightened my hold on her, slipping my legs down from the upward arch they were in behind her as she sat on me. As I straightened my legs out my foot brushed Zim.

Stopping my thrusting made Gaz aggravated and she tried willing me to move with her hostile demands but it didn't work. She resorted to trying to move herself but she couldn't because the lack of use of her hands took away her leverage. She wiggled on me and I pulled on her captive hands in incentive to talk.

She managed to free one hand and then the other a she pryed it from my grip. She placed them on my chest, ready to continue. I gave up fighting her and she got her way, just like she always did. I came in her, accepting that it happened, and Gaz used my still hard dick to complete herself. Her dull nails dug in to me and her face was so much different in the throws of orgasm.

She turned her face away as she fought the need to moan with her finish. Her purple hair was sticky with hairspray and sweat, hiding most of her expression. I was worn from my own orgasm and I still wanted to question Gaz. But I was tired, and didn't know where to begin. So I laid back with Gaz still sitting on me, fully aware that this didn't end here.


	3. Chapter 3

AUTHOR'S NOTE : Thank you so much again to my guest reviewer on the fan fic site :) I appreciated the kind words so much. This chapter isn't as exciting as the previous one but the next one will be better. Got some plot to fill in.

Any feedback will be greatly appreciated. Thank you for reading!

Three long slender drummed on my barefoot to get my attention as I looked up at Gaz who all of a sudden didn't want to look at me. She'd done nothing but look at me before, now it was like she was temporarily trying to erase me. If she didn't see me, I didn't exist. It'd been that way for a long time...and it never bothered me until now.

Having been ignored daily by her, the sudden attention was refreshing. It was different from the bored and inconvenience way she would regard me.I didn't like the dejected feeling that came with the abrupt withdrawal of her attention and I ignored the tapping appendages on me, instead I touched Gaz's thigh. Just as I had done to her earlier, she grabbed my wrist before I even touched her.

She was breathing heavily, still coming down from the sex. Her hair was covering the profile of her face as she kept her eyes on the carpet while looking away. Even as I was still physically inside her, she wouldn't let me touch her with something as innocent as my hand. It was strange, but not unlike her. My sister was complicated.

I tried touching her with my other hand, knowing better than to do that. She swatted me away and the three fingers on my foot tapped me again more insistently. Without even thinking about it I shook them off like a nuisance. I brushed away Zim like a common housefly.

"Gaz, what the hell?"

She said nothing, and she did nothing. Just sat there, her plush backside hot and pressing down on my pelvis. She was thinking about something, I knew that much. Trying a third time, I put my hand on her thigh and she slapped it so hard that a sharp, fleshy snap resinated.

"Don't touch me" I was scolded like I did something I knew I shouldn't have.

Had we not been in the position we were in I would never have grown the nerve to place my hands on my sister. It was common knowledge not to touch Gaz, Dad didn't even touch her. Not that he was even around much. Her boundaries were blatant but she started it, I wasn't out of bounds. That's what I told myself and even so I still felt stupid.

"Kind of late to be saying that..." I muttered

"Just shut up"

I was surprised how uninvested the command was, she said it like she didn't really mean it. I was right, she knew it. After doing what we did it was ridiculous for her to be mad that I touched her. She'd never admit that.

"Gaz" I said it quickly, as if I'd tried getting her attention once but hadn't been heard.

There was a moment of hesitation but she turned to look at me. Her blue eyes were sharp as always but without the threatening edge they usually held. It was so much easier to look at her when she wasn't cutting me apart from a distance.

"What is it Dib? What do you want?"

"An explanation would be nice."

She leaned down toward my face, forearm flat on my chest. The ends of her purple hair brushed my collarbone, and I could see where her pupils bled in to the blue of her irises. She was that close. She didn't validate my request with an answer, she shrugged, then laid herself flat on top of me with her face near my neck.

The three fingers I felt earlier returned to my foot, grasping my ankle. Feeling my stomach drop, I sat up a few inches to look at him, effectively starling my sister who held on to my shoulders in fear she was going to fall. She glared at me but I ignored her, feeling like an asshole for brushing Zim off earlier.

"Zim, I'm so sorry-"

" Gaz...she is offspring of the same genetic pool you were conceived from, yes?" He asked me, understanding that I just had sex with my biologically related sibling. "Is such behavior normal here? Breeding within the same gene pool?"

I felt like the answer was obviously 'no' but taking a step back I realized Zim wasn't familiar with societal taboos...rather the societal taboos of Earth. He was asking me earnestly, not knowing that Gaz and I just committed frowned upon incest. Although I froze up at the question, Gaz wasn't visably bothered. Infact, she answered Zim for me.

" No Zim, it's not normal...Dib and I aren't normal anyways. We aren't breeding either."

Zim crawled towards us, and Gaz craned her neck back to look at him. Her head moved as she watched his approach, following him as he crawled past her. He sat by my head and blinked down at me and then up Gaz. I imagined he was wondering if I Gaz was in heat too since he didn't have sex solely for the enjoyment of it. His body forced him to want it.

"Dib...does Gaz not wish to have smeet?"

"Smeet? " Gaz repeated, not understanding. 'smeet' wasn't the terminolgy I used in my logs. "What the hell is that?"

I dragged myself backwards to sit next to Zim, letting Gaz stay where she was being she showed no sign of getting off. She wobbled a bit as I moved but remained planted. I was going to clear up her confusion regarding 'smeet' when she flipped her hair back, indirectly making her small breasts move. I stared, snapping out of it, not missing the eyebrow Gaz raised at me.

"Uh..'smeet' is Irken for 'babies'." I explained it to her as casually as I could, knowing Gaz's cervix was currently coated in my semen. My very fertile semen that should have been contained in a condom. "Guess I should add that to the reports at some point.."

"No Zim, I don't want any smeet..." My sister told him, finally rearing up on her knees to pull herself off of my dick. "I need to get up"

This was all very new to Zim, the information. He didn't understand why she partook in sexual activity with me but didn't want to bare offspring. Being the ever straight to the point type that he is, he brought it up as Gaz lifted herself off me. He watched my erection slide out of her, seeing the globs of ejaculation slide out from inside her and down my shaft.

"Is that not the purpose of human intercourse? To produce smeet?" he wondered, moving over a bit as Gaz climbed past him to get off the bed. " You have accepted his seed. It is inside. "

His seed is mine

"I'll be back"

My mind flashed back to Zim's incident with Gaz and I snapped my head to the left to look at him. He was watching Gaz walk to my bathroom, a white trail sliding down from apex of her thighs towards her knee. She didn't shut the door, I assumed it was because we couldn't see in it from on my bed. The toilet seat shifted with her weight and the light trickle could faintly be heard as she urinated.

"Hey, uh Zim... how are you feeling?"

"Zim feels fine. The heat has calmed...burning no longer consumes Zim." He assured me, facing the direction Gaz left in. " Gaz does not wish for smeet ...Has Gaz also sought out your assistance with her reproductive ailments? Does the heat also plague Gaz?"

The toilet paper roll was being spun in the bathroom, sounding like Gaz was cleaning up the remnants of me from her inner thighs. The toilet flushed and the sound of water running followed after.

"I don't know..." I lied to the irken, knowing very well that my sister wasn't suffering how Zim did regularly. "Speaking of heat, what happened earlier?"

"What does Dib speak of?"

"You freaked out...on Gaz. You almost attacked her"

Speaking of the devil and he will appear. My sister emerged from my bathroom, making no attempt to cover herself. She didn't shy away from Zim or I's eyes. Zim had only ever seen me naked, so he didn't know what women looked like . For us, Gaz's body was fascinating on two different levels...my level being admittingly shameful.

Checking out my sister wasn't something I did...regularly. When I did look at her it was a passing fascination. I wasn't around women a lot, so when she walked around the house in a oversized hoodie and nothing underneath I couldn't help but follow the expanse of her legs up to the curve of her thighs and know what was underneath the baggy material hanging over her upper thighs. It wasn't a lustful stare, just fascination.

"Zim does not recall such events.. Zim's memory is lacking"

The Irken was looking at her breasts like they were extra appendages. Gaz sat down by Zim's criss crossed legs and he continued to blatantly look at her chest. He tapped his chin with one finger and pulled it away to poke her. All I could picture was the poor clueless alien getting decked in the face but to my complete amazement Gaz sat there and let him prod at the mammary tissue.

"What did Zim do? Zim would like to be enlightened of his treatment of the human Gaz..."

Zim's strange behavior hovering in the forefront of my brain, I watched him poke her right breast. His very slender finger poked it, indenting the pillowy mound. The dimple he made filled itself back in when he stopped poking. His attention was then drawn to the dark pink bud in the center and he poked that too. Gaz sucked in air as his almost claw like finger touched the surface of the rosy peak and Zim pulled his hand away in surprise, curling them in to his palm

"You can touch it" It was so strange to hear her say it. "I just wasn't expecting you to...Go ahead"

I really wanted to question Zim about his apparent blackout, but I was becoming increasingly immersed in what was taking place before me. Zim tapped two fingers together almost like tweezers, and squeezed her nipple with his fingertips pinching her vertically. I watched as he then move on to slide the jewelry through the horizontally pierced skin and that's when Gaz caught me gawking.

"What, do you want to touch too?" She asked, the question being completely legit. It wasn't threatening, or sarcastic. Just straight to the point

My first instinct was to shake my head 'no', and that's what I did. I wasn't ready to lose my fingers.

" You're a horrible liar"

Gaz turned her attention back to Zim as he began taking his hand back from her chest. She stopped it, holding his hand in hers and touching the elongated green digits. She separated them, bending them at the joints slightly and rubbing the tapered tips. Zim wasn't bothered.

As she inspected his hands I began noticing the way she warmed up, her body language the smallest bit more approachable. She was still the apathetic, unapproachable sister I'd always known, but the physically boundary I'd always known her to have was being dissolved right before me as she interacted with Zim of all people...'people'. Gaz twiddled with Zim's fingers, her lip curling in almost unnoticed as she gnawed at it lightly from insider her mouth.

I was left speechless as she splayed his hand open and brought it to her breast, making Zim curl his tapered digits on her breast, cupping it. The Irken didn't know what she was doing and neither did I until I saw her lean in to him. She was going to touch his phallus and I reacted in an instant, getting my voice back.

"DON'T" I yelled, interjecting. "Are you crazy!? You saw what he did earlier!"

Zim jumped from my volume but Gaz didn't.

"So you're just supposed to have all the fun?" Gaz accused

"What? How was him hissing like territorial animal fun?"

Gaz didn't respond and retreated away from Zim. The Irken wasn't bothered that she tried touching his semi erect phallus, he didn't hiss or growl. He didn't even remember trying to attack Gaz and that still puzzled me. My sister getting up and picking up her clothes on the other side of the bed puzzled me even more as she collected them and left without a goodbye.

"Human Gaz has left" Zim stated, looking at the closed door. "Why?"

"I don't know, Zim..."

He cocked his head side to side very shortly, then looked for his own clothing. He stood up and I stared in amazement at how much the Irken had really grown in the last year. One shot I had concocted in my freshman year of college became a series of treatments and he grew like a weed. Because of the hormonal treatment, he was past five and a half feet now. Now at five foot five foot eight, he was far taller than his original height of five feet. . . but unstable.

"You going to stick around for me to shower?" I asked him, wishing he'd get back in bed and hug me or something. Comfort me like a partner. Anything "You could lay with me or something."

"Zim must return home to his work."

The dynamic I had was Zim wasn't what I wanted it to be. I didn't want to be the sex toy he relied on to satisfy his vengeful hormones... even if they were my accidental doing. I watched him pull his clothes on his body, covering the almost matte green skin. It's ridiculous how attracted to him I am, it was even more ridiculous how frustrating the unmutual feeling was. He didn't know.

Zim was very anthropic but that wasn't what attracted me to him. I didn't need to look past his alien traits to become aroused or satisfy myself sexually. The fact that he was an extra terrestrial interested me. Years of my adolescence being a space nerd influenced my sexual kinks and by the age of sixteen I found myself filling my web search with xenophilic images. By then I gave up my feud with Zim. I didn't want him captured. I wanted him to be mine. So we had a truce because by then he began understanding the disadvantage he had on Earth.

"Zim you should stay, I still have to collect your samples and run them. You had an episode, remember?"

"Zim does not remember but Dib may enlighten Zim when we meet next. My communication module needs tending to."

Contacting the armada was all Zim concerned himself with now. He didn't care for invading the planet anymore, he claimed he just wanted to go home. If he really wanted to go home he'd find a way, but in his condition he knew it was not the best idea. So he stayed on Earth, with me.

After Zim left I took a shower, muttering to myself about his behavior. In the next room over my sister was doing something, most likely pretending I didn't exist like before. She stayed in her room as Zim dressed himself, putting his wig and blue contact lenses back on, before leaving. I would have much rather kept him for observation but I didn't have the energy to convince him

Out of the shower, I left my bathroom still sopping wet. I hastily dried off, distracted by my racing thoughts. Mostly dry, I dug around my dresser for a pair of pajama bottoms and a cotton shirt. I put them on and swiped the hand held recorder from the drawer in my desk and set it next to my lap top.

The desk chair was still turned, facing my bed, just as Gaz had left it. I I turned the wooden seat back around and sat down in it, opening my laptop with a dismissive sigh to the frazzle thoughts drifting through my mind about my sister.. I pulled up the word doc on my log, going over my findings in the previous years. I focused on the ones exclusive to the previous year being that's when I took an interest in the Irken race's reproduction.

" Tuesday: Log 1 Problem with Zim" I spoke in to the recorder after pressing the button. I set it down to record as I looked through my documents. " Irken specimen shows sexual aggression without warning. Variable to blame is unknown"

All my logged reports showed consistent behaviors during colitis and after. Zim's body would warm with hormonal heat, and he'd seek relief from me. His buttocks and face would flush, his anal opening would close tightly after orgasm and he would fall in to a sedative like recovery as his body awaited the fertilization of his eggs.

"Attempted stimulation of phallus appeared be trigger of behavior, theory inconsistent with previous studies."

When attempting stimulation of his phallus, normally he would reject it with a soft spoken plea for me to let go. Earlier, he hissed me at me. He also tried attacking Gaz. The incident didn't fit in to the usual equation and what concerned me more than the aggression was the fact he didn't remember. I sat there for an hour going over logs, hoping to find some note or variable that I'd missed.

" Blood sample will be taken to rule out possible hormone fluctuations "

His hormone levels were always high but they didn't fluctuate any more than they initially had after his treatment. I checked his blood in my lab downstairs every week, keeping track of any possible changes that could happen. As meticulous as I was about my data, I was at a loss. I would need to check his blood and fluids later if he came back, tomorrow if not. Sexual activity never riled up Zim like that. The clock in the house tolled four and as I counted them I felt like I was missing something.

My stomach gurgled with rising hunger and I realized that I skipped lunch. Gaz came home around noon when I was busy with Zim so I hadn't had a chance to eat. With all the commotion I didn't feel hungry, but I was now. Not wanting to step away from my data, I picked up the recorder.

" Specimen requested seminal fluids, followed by hostility towards ..." I hesitated how to phrase Gaz in the audio. "...an observational sit in. Specimen claims to have no recollection of the specified events. "

I left my bedroom, verbally recording the information to be physically logged on my laptop later. Walking past Gaz's bedroom door to take the stairs downstairs I noted with intrigue that music was playing. She always had headphones on, her stereo was seldom used without being connected to her headpiece. Clicking off the recording, I knocked on her door while passing out of habit.

"Are you hungry?" I called out to her, cringing as I realized it may not have been a good idea to bug just yet. I continued to the stairs quickly in fear she'd rip the door open. "I'm heading to the kitchen..."

As independent as Gaz was, Dad still expected me to make sure she ate. She spent half her grocery money on a videogame ONCE when she was fourteen and Dad thought it would become a habit. He never cared about us but stressed that I fed Gaz, even at seventeen. I, a nineteen year old, was in charge of making sure my seventeen year old sister ate. I swung open the fridge, seeing almost barren shelves. A gallon of milk was half empty on the top shelf, some bread next to it.

"Dad left the grocery money in your account, remember?" Gaz said from somewhere behind me, walking In to the kitchen. " The fridge is basically empty."

" Shit, you're right..." She startled me with her presence but I was happy not to hear any anger. She randomly just got up and left earlier.

"Is there anything in the pantry? Or are am I food shopping?"

The pantry was opened, revealing a box of cereal and few boxes of mac and cheese amongst other random non perishable goods. Nothing substantial. Gaz did a double take at the boxes of mac and cheese.

"I didn't know we had mac and cheese..." she grumbled, looking up at the boxed macaroni high on the shelf. "I ate the gross cafeteria lunch today for nothing. I could have just ate here"

Gaz was very petite, measuring in at almost a whole foot shorter than me. Being only five foot two inches tall meant she couldn't reach high shelves. If she wanted something she would get a stool or just climb the shelf with difficulty. She jumped up to grab a box of mac and cheese but missed it.

She used a kitchen chair to reach it before I could go over and get it down for her. The macaroni rattled inside the cardboard box as she threw it down to the table, sliding a few inches across the oak surface. That was her way of asking I make it for her. She was only two years younger than me but I still cooked for her when she perfectly capable of learning to do it herself.

"What did you have?"

"Some gross pizza" Gaz complained flatly. "The lunch is horrible on half days, it was burnt. The cafeteria ladies are incompetent."

The audio recorder I held needed to be put aside to make the mac n cheese so I put it down on the counter after I took the milk from the fridge. I asked Gaz to toss down another box and she did without complaint, the second one almost hitting my hand as I reached for the box already on the table.

"I didn't mean to do that" she promised, getting down from the chair but not before snatching a plastic tube of crackers off the shelf. "You were in the way, dib shit"

The plastic tube of crackers crinkled as it was torn open, Gaz getting in to it as soon as she was back on the kitchen floor. Cracker in mouth, she chewed it between her back molars as she dragged the chair back to the table. After taking a pot from the bottom cabinets, I decided to move my recorder to the table to prevent it from getting wet when I filled it in the sink with water.

She stopped chewing for a second as the clunky old fashioned device was put down across from her. She resumed eating the crackers, reaching out to take it when I wasn't looking. She turned it in her hands, impassive towards the obsolete piece of technology.

I filled the pot with water and set it on the stove to boil. Both boxes of mac and cheese on the counter next to the stove, I turned around and rested against the counter. I saw Gaz fiddling with the recorder as I looked over to ask her what she would want when I did the food shopping.

"I'm probably going to do the shopping tomorrow, is there anything you want?"

"I'll just go with you" she asserted, tapping my device on the table top for whatever reason. "The plastic on this feels like my childhood handheld. How old is this?"

"That used to be Dad's, Gaz. It's pretty old... and I was planning on going after class. I get out at noon, you don't get out until two."

"Then wait for me"

The water began boiling so I opened up both boxes of macaroni and poured them in the pot. When the food was done I dished it out in to two bowls and brought them to the table with spoons in them. I took the recorder from her hands and she almost didn't let me have it.

"Why the interest in this?" I asked her, putting the device down away from her so I could eat in peace. I didn't want her to accidentally erase anything by fiddling with the buttons.

"No reason"

"Uh huh..."

Gaz began eating first, spooning macaroni in to her mouth while looking down at the bowl. I'd eaten meals with my sister my whole life but all of a sudden I felt like I didn't know to act. Getting food in my mouth was almost robotic as I focused on trying to be normal when something hit my leg. Apparently Gaz was trying to get my attention but I didn't hear her.

"Earth to Dib, I'm talking to you"

I coughed on the food that nearly went down incorrectly and hit my chest with a fist as it made Its way down. Gaz was twirling her spoon in her fingers, watching me. When I brought my eyes to meet hers, she put the spoon back in her bowl .

" I need a favor."


	4. Chapter 4

AUTHOR'S NOTE: Sorry about the wait! I have multiple stories I'm hopping around between. To my reviewers, I was so thrilled to see you left reviews. Thank you, thank you! I'd love more feedback, it keeps me motivated. You're all great!

"I need a favor"

Never at any point did I think my sister would put me in such a position.

Sitting in the passenger seat of my car, she held out a folded fifty dollar bill to me. I took it, glancing at the adult shop centered in the parking lot. Brown shades adorned the windows with a very clear "18 and Older Only" sign hung on the entrance door. I looked back at Gaz, and she was as casual as one could be.

"I ordered the package online under your name, it's on hold behind the counter." She explained to me. " It's not paid for so just ask for pick up and they'll ask for your name."

"What exactly did you order?" I asked in concern, worried that whatever Gaz ordered was going to leave me looking fairly odd..er. I didn't have a good reputation. "Because if they're scanning my I.D-"

"They're not gonna scan your I.D Dib shit. They're just verifying you're eighteen. Grow a pair"

The inside of the shop was far less intimidating than I anticipated. A girl in her twenties stood at the counter and waved at me when I stepped in. Her hair was in a high ponytail, the strawberry blonde curls spiraling down past her shoulders. The sign above her head said 'Pick up and check Out", so I walked over.

"What can I help you with?" She asked, hands on the counter. " Looking for something in particular?"

"I have a package on hold..."

The girl nodded and asked for my name before going under the counter to look. I waited for something lewd and sexual to be pulled out in a vibrant sex toy package but what I saw was the opposite. She pulled a brown cardboard box, the postal label from the warehouse still stuck to it.

"Whatever this is I guess we don't carry them in store" the employee stated, putting the package on the counter. "I.D please."

"Here..." I pulled my I.D out and handed it to her.

"All set. " She checked the name on the box then my card, handing It back to me. "Let me just scan this bad boy up and you can be on your way."

Typing in the package code, apparently the price came up but not the product inside. The cashier wanted to know what it was, skimming the screen for information but the product didn't come up. I could almost feel sweat pooling in my pores as I worried the contents of the package would be revealed and make me look weird or like some pervert. Gaz was going to be the fucking end of me.

"That'll be thirty eight dollars and twenty two cents with tax" she informed me and I handed her over the fifty dollar bill. "Thank you, Sir."

She punched buttons on the register and It slid open. After she put in the money and collected my change, handing it to me with a receipt. The package was picked up and she placed it in a bag for me, the plastic a simple black color. Very discreet, which I was grateful for.

"Have fun with whatever this is" the woman winked at me, waving goodbye as I left.

When we got home Gaz didn't talk about the package. She took it to her room and that was the last I saw of her that night. Zim didn't come back either and I stayed my room to continue my research, shamefully curious to what Gaz had bought. Whether she was using it or not was beyond me.

Xxxxxx

" Dib I'll be right back"

Gaz wandered off as I picked some boxes of pasta off a shelf at the supermarket. I turned my head and saw her walking away down the aisle. Her converse made almost no sound as she walked down the shiny tiled floor, her head of purple hair disappearing as she rounded the corner out of the aisle.

"o-kay..." I said to myself because she was already long gone, her not waiting for my response.

I took cans of pasta sauce and placed them in the cart. Walking down the aisle I grabbed some macaroni and cheese, ramen and other instant noodles. Bread, milk and eggs already in the cart I turned out of the aisle when spotting Gaz walking back. She had small boxes of gelatin mix ...a lot of boxes of gelatin mix. I knew she liked it but we usually just got the premade cups.

"What's with the gelatin mix?"

"Don't worry about it"

Gaz dropped the boxes in to the cart. The small boxes tumbled in from the pile in her arms and she walked off once empty handed. I followed her and we wound up at the cereal aisle. She walked, scanning the shelves and I stopped to grab what I wanted. I set it amongst the groceries and looked up, seeing my sister struggling.

The box of cereal Gaz wanted was on the highest shelf and she couldn't reach it. She dug her shoe into the shelf closest to the floor and held the next highest one up with one hand, anchoring herself to climb. My sister was short, and very proud.

"You're gonna hurt yourself, Gaz" I warned her, knowing she wouldn't head my concern at all. "There are better ways of going about that"

"Not everyone's six feet tall, Dib"

I walked up behind her and plucked the box of cereal she wanted from the shelf and placed it in the cart. Instead of thanking me , she got down from the shelf and she punched me in the stomach. It didn't hurt, which was surprising. Her passive aggressive blows usually held more punch to them, usually at least knocking some wind out of me.

Through the supermarket we went, grabbing food for the week. Gaz had to have her candy, her soda and her snacks. I rested against the cart as she gathered what she wanted. I thought we were done as we walked towards the checkout but Gaz turned sharply in to an aisle. I stopped the car quickly and watched her walk down the personal health aisle.

I hesitantly followed her once redirecting the cart and I saw Gaz standing at the 'family planning' shelf display. My heart seized in on itself, shooting up to my throat as my eyes landed on the pregnancy tests. The first thing I thought of was the lack of protection I'd used with Gaz.

"Do you need...one of those?"

My sister shifted her eyes over to the pregnancy tests and shook her head. She picked up a small box instead and tossed it in the cart.

"I need that"

My sister needed the morning after pill, lovely.

She took it as soon as we got home. The grocery bags were dropped on the kitchen floor and she rifled around for the box. After getting it, she found the bag with the soda in it. She popped open the cardboard box and took a can of cola out. I pretended not to pay attention, putting away some groceries as she set the soda can down on the table and tore open the box for the pill.

I could hear the crinkling of the plastic pouch inside as she opened it, then the snap and fizz of her opening her soda. She took a big gulp, swallowing it, and then set the can back down. We didn't say anything about it, and she began helping me put everything away. I tried putting the bag of gelatin mix boxes in the closet but she took it from me and dug out four before letting me put the rest away.

She was reading the directions on the box and I was prepared to help her but she already set about getting the pot from one of the cabinets. She filled it with water, presumably estimating the measurement. I watched her for a minute and she caught me. She shifted her eyes back to the filling pot.

"Don't you have something to do, Dib?"

"...No?" I second guessed myself, pondering if I had something that needed to be done. "...I don't have anything to do."

She shut off the tap and placed the water to boil, looking down at the pot silently. I stood there, not knowing what to say or do. I should have walked away like a normal person but ...I didn't. Gaz glanced over at me, her eyes bored. She piped up vaguely curious though.

"So where's Zim? "

I thought about it, taking in to consideration how valid of a question it was. Zim was over a lot and he didn't come back yesterday, and he hadn't shown up today. Naturally his missed presence would go noticed. Gaz didn't ever ask about such things though, not in the past.

"He's most likely at his house, I haven't heard from him yet."

"oh." Gaz paused, speaking up after a second. "I see"

Gaz shifted her gaze away from me, looking back at the pot of water on the stovetop. With apparently nothing else to say, that was the end of that conversation. Retreating back to my room without ceremony, I climbed the staircase and shut the door behind me when in my room. I could hear Gaz walking up the steps shortly after, and then her footsteps as she passed my door. I froze for a second and then her bedroom door opened.

I breathed to calm myself, my heart palpitating anxiously, and went about my business taking my shoes off by my bed. I dropped my coat over the footboard and sat down, taking my glasses off. Rubbing my eye, I froze again as I heard the unmistakable sound of a cardboard packaging being opened. I heard packaging tape being torn off, the scratchy rip carrying through my wall.

I could practically visualize my ears perking up as I listened. Whatever she ordered came in styrofoam beads because I heard her rummaging in the box then an airy crunch as she stepped on something. The perverseness of what I was doing did not slip by undetected by me, I realized how horrible it was that my sister's adult purchase fascinated me so much.

Whatever she bought had multiple parts because I heard her drop three things on her bed, tossing them one at a time. She opened all of them and then just as soon as she finished, she was leaving her room. Upon hearing her walk past my room again, I felt my face warm. Collecting myself, I got up and sat at my desk with my laptop.

Gaz never came back upstairs and it took all my willpower not to go snooping in her room. She'd hear the door open and if that happened I was doomed. I'd heard Gir's stupid Doom song so many times and if I dared step foot in Gaz's room without permission the little robot would surely come flying in the damn house and belt out singing.

Hours passed with nagging curiosity that I forced myself to stuff down. As the afternoon ticked away evening rolled in and it was dinner time. I saw the time on my computer screen and wondered what was going to happen for food that night. Gaz would expect dinner soon and Dad sure as hell wasn't going to be home to make it. Neither would Gaz. I wondered why Gaz was willing to take the initiative to make gelatin but wouldn't learn to cook anything else. Wasn't going to ask her that though.

As I thought of Gaz I couldn't repress the returning curiosity I'd had earlier. So very badly I wanted to know what Gaz had sent me in to the adult shop. She'd made me go in, surely it wouldnt be too much to let me in on what it was she'd bought. Knowing my sister, asking could possibly also lead to doom. I was better off leaving it alone.

The stairs creaked as Gir's obnoxious verse played in my head, remembering one of many days he ran around Zim's house screaming for hours on end. I assumed Gaz was going to come knocking for food. I heard her approach the door and then stop. I stopped and listened, then there was a knock.

"I'll be right out" I called out to her. "Dinner-"

My door opened and Gaz came in balancing two plates on one arm as she turned the knob. The door opened and she bumped it with her hip. My eyes were drawn to the plates of food she carried in and I blinked in surprise. Very sincere surprise.

"...is sandwiches?"

My sister never made me anything to eat in my whole life. But in her hands were two plates, both with sandwiches. There was a bag of chips under her arm and she held it to her side with her elbow as she neared my desk. She put one plate in front of me and then stalked off to my bed, sitting down with her plate and the chips.

The bag of chips was opened, the air released with a pop as she tore open the top. I looked over at her and she just ate some chips, the crispy potatoes being crunched between her teeth loudly in my otherwise quiet room. She knew I was looking at her and she kept eating, looking straight ahead.

"You not hungry?"

"Its not that.. Um, thanks for the food"

"Yup"

Normally it would be rude to ignore the person you were sharing a meal with, but in our case it was far more common not to speak to one another. Eating together didn't actually mean we actually partook in a meal together. For years I shared meals with my sister, the majority of them she spent without so much as trying to humor me with conversation.

Accepting that this was no different, regardless of the unusually considerate gesture on Gaz's part, I took a bite of the sandwich and returned my attention to my laptop. I was nearly done with my sandwich when I heard Gaz get up from my bed. Her socked feet dragged across my carpet and I felt a little zap underneath my ear.

Gaz had poked me, zapping me with the static she'd gathered from the rug. I flinched and she didn't say anything, just sat herself down across my lap. I paused, unsure of what to say. Gaz reached her hand in to the bag of chips she held and brought one to my mouth as she peered down at my computer screen, reading over my notes.

"Want some chips?" She offered distractedly as she read, very immersed in Zim's charts.

"Sure..."

I took one from the bag and ate it as Gaz continued reading. She hummed montonely before pulling back from the screen and leaning in to me as she munched on the chips again.

"So Zim can get pregnant... how'd you figure that out in time? You're lucky you figured it out before accidentally impregnating him."

"Yeah you can say that again...I figured it out during an invasive examination. I already knew he produced semen...then I found his egg pouch"

"So are the Irkens a hermaphrodite type race or whatever?

"So far that's what my research has concluded... they breed based on dominance. The superior impregnates, the inferior becomes impregnated...Zim's permanently the inferior now. Not unless I can regulate his hormones again. "

Gaz's interest was peaked at my in depth explanation of Zim's anatomy, questioning how I'd planned to do it because I hadn't written out a plan yet. If I had, she would have already found it amongst my logs and read it.

"His body think's he's female...his hormones are horribly unbalanced. I warned him that the experimental drugs could backfire but damn it Zim wanted to be taller...he wouldn't listen to reason." I mumbled to Gaz as she listened closely. "I have to counteract the effects with another drug, I just don't know what yet."

"I'm assuming you're counteracting the first drug with something to cancel it out, right?"

"Pretty much...or I need to supplement his body with the missing hormones to fix the imbalance. Shit this is going to be hard."

My sister ate another chip and mulled the information over.

" He can't go home like that" she mentioned. "That'd be a disaster."

"Precisely...he's stuck here until I can't fix him."

"It could be worse."

I nodded in agreement. I didn't want Zim to leave anyways. It would be better for his health to fix him as soon as possible but I wasn't exactly trying to send him back home. Still, I'd do all I could to ensure he wasn't stuck the way he was. Even if it meant he'd leave Earth.

"Where is Zim anyways?"

"I still haven't heard from him. I'll check in with him tomorrow I guess.' I muttered somewhat gloomily. "I'm not in the mood to go chasing him down."

"Are you in the mood for dessert?"

xxxxx

When Gaz returned to my room I expected a bowl of gelatin...and that's not quite what I got. She walked in and wore nothing but her eggplant purple shaded undergarments, a tray of something in her hands and some sort of elongated funnel I couldn't really see. She approached me as I sat at my desk stunned.

She lowered the tray that I could now see what a gelatin mold. Inside the tray were six, shiny yellow oblong orbs of gelatin. I stared at them, feeling myself become aroused with a familiar pubescent interest. Set the tray down on my desk and plucked up one of the orbs of gelatin, holding it out for me to see.

"I'm sure you know what these are" she goaded me, jiggling the mass, the slimy texture catching the light perfectly. "Or rather what they're supposed to look like."

I nodded, swallowing heavily.

"Alien eggs..." I nearly croaked, my eyes sliding over to the item in her hand that I could now see was a fantasy, Hollywood movie based alien phallus toy.

The elongated funnel like toy was tapered down a narrower opening than the base was. The silicone was smooth and painted green, a color so much fucking hotter than red. Red was overrated. So overrated. Gaz twirled it in her fingers almost like a Baton and my breathing picked up as I watched her bring the faux egg to her lips.

"They're made of Jello" she commented unnecessarily, slurping the surface as she took a bite of the large mass. " You like lemon, right?"

It's only my favorite.

I could only nod my head in response to my sister and she held the gelatin egg she'd bitten in to out to me. She raised it to my mouth and I took a bite, Gaz smirking as she purposely ensured I could see the alien phalus she waved around her fingers. She straddled my lap, facing me, and very confidently slurped down the rest of the egg. Lost in the erotic display, I didn't even care that my pants were suddenly way too tight or how wrong it was.


	5. Chapter 5

AUTHOR"S NOTE: Hey, thanks for reading and thank you for the reviews! You guys are so nice! Hope you enjoy :)

Xxxxx

I looked up at my sister helplessly and her fingers wrapped around my neck. She locked eyes with me and brought our faces in close together. I braced myself for her lips to touch mine, but they didn't she averted her lips, slowly bringing them out of sight. Then her breath was on my ear, and she clicked very lowly. The sound in her throat.

"Fuck!"

Gaz laughed at my outburst, completely satisfied with herself. After dropping the toy she had on my desk, she bit my ear and I clenched my fingers on the seat of chair, eyes nearly rolling back in my head at the sweet feeling of her hot thighs in my lap. My erection strained in my pants under the apex of her legs and she nearly tore in to the cartilage as I groaned.

"Are you gonna touch me or not?" She demanded, rearing back to look me in the eye. "Fucking touch me."

Without thinking I grabbed her ass, squeezing it in my hands. Gaz wedged her hands between our bodies and took the hem of my shirt in hand. She roughly bumped my arms away with her elbows so she could lift my shirt off me. As she threw it aside I hesitated to touch her again but she placed my hands where they were, bringing our chests together.

Again, I thought she'd kiss me. And she didn't. Her mouth went to my neck, biting down on it. I choked at the contact, unable to comprehend what was happening as Gaz ground her hips down in to me. Humping me through my pants she quickly became impatient and stood up. I didn't let go of her ass and she ripped my hands away from her.

She turned herself around and bent at the waist over my desk, quickly picking up the alien phallus toy. She slipped a gelatin egg inside it and held it between her legs, letting her panties fall to her ankles. The underwear was kicked aside and she penetrated herself with the phallus.

I watched as she squeezed the plastic, seeing the egg move through it. It entered her and she gasped, presumably at the cold tempature of the gelatin. The toy was removed. She craned her neck to look at me from over her shoulder and dropped the toy on my desk.

"These melt fast" she informed me. "Dig in."

I'd never been quicker to get on my knees. Behind Gaz, I had my desk chair pushed far back behind me in a quick shot of my arm. Getting low behind her, I looked up and saw her intimate lips wet with the melting gelatin. The syrupy sweet liquid beginning to ooze. Gaz spread her lips wider, readjusting on my desk and I dove in as a drop leaked from her.

"Shit! Dib-"

Gaz gasped, cussing as my tongue met her flesh. I could feel the tip of the egg on my tongue and I licked at it, teasing her entrance in the process. My sister breathed heavily as I licked at her, the gelatin slowly melting. I lapped up all of it, feeling around her flesh.

My fetish getting the better of me, I probed around to feel the egg. How heavy it was on my tongue, feeling the slimy consistency wedged within her walls. The way her entrance struggled to keep it in, contracting aganst the slippery mass...it drove me crazy. Apparently it drove Gaz crazy too.

"Dib, I can't keep it in..." Her thighs tightened with the struggle, fingers reaching between them to touch my chin. "Fucking eat it!"

Mouth open, I obeyed my sister. I slurped at her entrance, sucking in the gelatin as her body released it. Above me I could hear Gaz huffing, breathing heavily as my tongue licked her. Doing her best not to give me control, she maintained her composure.

If I'd had the clarity to think about it, I would have realized I technically had the control. But with a faceful of my sister's crotch and a mouthful of both her and the gelatinous juices, I didn't care about control. I cared about her...ironically that itself gave her the control.

My sister was a bitch, I never saw her actually happy. Especially not with me. But with my mouth between her legs she was having a blast, because of me. The fingers on my chin pushed more firmly, confirming it. I didn't know what the hell I was doing, but I grabbed her ass cheek with one hand and snaked my other between her legs.

I knew of the clitoris but searched for it blindly. My sister caught my wrist startling me, and slurped at her harshly. She cussed but still held my wrist, guiding it to where I'd been looking. Too immersed in the wet, hot flesh in my mouth, I wasn't embarrassed in my failed conquest to find her clitoris. I was relieved when she placed my finger tips on it.

"There, is that what you were looking for?"

I nodded in to her and I could visualize her eye roll. Even with the suspicion I may have annoyed her, I began to touch her. I rubbed at her, feeling her ass quiver as I sucked up the last of the gelatin egg inside her. With none of it left, I didn't know what to do. So I did what came naturally, I kept licking.

Inside her I moved my tongue, tasting the remnants of lemon mixed with a distinctly semi sweet flavor. As I felt wetness still reaching my tongue I realized it was her I was tasting it. It was amazing and the thought of it being shameful didn't pass my mind just then. It completely evaporated out of existence when I heard my sister moan, the sound ripping from her lips. She didn't bother being mad she'd caved or even try to cover it up.

"Dib, don't you stop" she warned me, fingers tightening on my chin. "Don't you dare stop. Fuck!'"

Inside my pants I was throbbing, painfully confined. But I didn't dare stop to think about relieving it. My sister was priority. Even without her warning. So I did as I was told, I kept going.

My fingers on her clit slid through copious lubricant, massaging the pearl with ameteur and blind movements. Gaz didn't seem to care though, more invested in the feeling of my tongue inside her. She bucked her hips back on to my mouth, riding my face. Had my desk not been such a heavy piece of furniture, it surely would have rattled with Gaz's movements.

She held my face to her firmly and gave a loud wail as she came. I didn't move an inch or attempt to pull away. I stayed right where I was. Her essence was smeared along my chin and mouth, I could feel it. Gaz struggled to catch her breath and leaned over on my desk as her arms gave out a little.

I wiped my face, amazed at my sister's worn posture. Her complete satisfaction. Or so I thought she was. Because when I placed both my hands on her hips to get up, she reached behind herself and grabbed be me by a belt loop. Still bent over the desk, she blindly looked for the button to my pants. She undid it and grabbed my hardness through my underwear, not letting go.

"Get a condom" She demanded.

"You're-"

"What?"

"You're gonna have to let go first."

Gaz let go and used her hands to undo her bra instead. As It landed on my desk I turned to retrieve a condom from my nightstand. The foil square package in hand I approached her and she looked over her shoulder at me, to the condom and then raised her ass.

Shedding the rest of my clothes, I opened the condom and rolled it on. Feeling of latex on my flesh was a relief offering some reassure I hadnt had the previous day. Taking Gaz by the hip, I hesitated but quickly brushed away the uncertainty. Gaz knew what she wanted. She always did.

So without asking, I went in. I entered in and met little resistance to the penetration. Her fluids and my saliva coated her wetly, allowing me to slip in easily. Without simply plowing in to her, I began a heavy thrust. I was aching and eager, my loins still stirring from my earlier service to Gaz.

"You know..." My sister began, feigning composure. "You're a lot bigger than I thought you'd be."

At first I thought nothing of her remark. At first.

"Thought about it before or after you walked in and saw it for yourself?" I pryed, honestly curious."You know, when you 'forget' to knock all the time."

"Well aren't you nosey?"

"You're one to talk."

Gaz make a dismissive noise and pushed her hips back in to me, her attempt to shut me up. I didn't cave, I pryed more. Much to her dislike.

"What? You don't want to come clean to big brother?"

Before I knew what was happening Gaz pulled herself away from me. I stood dazed as she turned around. She hopped up to sit on my desk and wrapped a leg around my waist, tugging me in close. Her hands were around my neck and her sharp blue eyes were blazing despite her passive expression.

"You're not in charge here" she told me, simply. Straight to the point. "I am."

I wasn't scared of Gaz, not in the conventional sense. She was a tiny thing, a young woman of not many words. But looking down at her, she was easily terrifying. I could see why most didn't take to her. Not that they took to me either, but Gaz was an all around unapproachable person. But still, there I was. And her sharp tongue didn't phase me.

I didn't respond to Gaz's declaration of power. She noted it, along with my stare on her. She leaned back on my desk, taking me with her. Her face was right in mine and she stared at me. Her eyes still blazing. Her cheeks tensed.

"I'm in charge"

"I know" I assured her earnestly.

In some fucked up Hollywood movie I would have expected Gaz to stare at me and smile in satisfaction. But that wasn't my sister. I didn't expect any form of appraisal or reward. But I got one anyways. I got something better than a smile, I got kiss.

Her lips grazed my cheek.

Spreading her legs she reeled me back in close and I penetrated her again. I moved to her instruction, arching my body over her. Her fingernails dug in to my shoulders as I moved in her, her purple hair thrown back with her head. Her mouth opened as I jutted my pelvis against her, her breathing picking up again.

I was close and spiraling towards my own release. The arousal itself was intoxication, taking over, but the eroticism of my cold, domineering sister naked and panting on my desk was too much. Scared of losing it too soon, I tore my eyes away to the desk under her. Then my eyes landed on the left over gelatin eggs and I quickly returned my eyes to Gaz.

"Gaz-"

"I'm close too"

With an arm curled tightly around the back on my neck, Gaz arched her chest up in to me and pressed her pelvis against mine. Bumping with the momentum I'd set, she concentrated on reaching her limit before me. And she just barely succeeded. I came just seconds after her, nearly collapsing over her body. Leaning on the desk, still between her legs, I wiped sweat from my face.

"Shit, Gaz."

My sister shrugged and leaned back, resting on her elbows. She watched as I pulled out and I ignored her eyes as I stepped away to pull the condom off. As I chucked it in the garbage the house phone rang. Gaz got up to go get it and I let her, needing to use the bathroom anyways.

When leaving the bathroom I could hear Gaz talking on the phone. By the curt and monotone tone of voice I could only assume she was talking to our father. Instead of going to check, I put on my underwear. Plopping back on to my bed, I waited for her to come back and tell me Dad would be gone for the umpteenth week in a row.

I heard the phone receiver click and then Gaz's feet coming back down the hall. She was still completely naked, not caring. Of course her clothes were scattered along my desk but she didn't pay them any mind as she walked by and in to my bathroom.

"So how long's Dad gonna be away for this time?" I called out to her.

"That's a dumb question if I've heard one, Dib."

"Point taken."

Asking about Dad's whereabouts was a tiresome, redundant charade. I learned as a child not to expect Dad home. It sucked though for a while. Not having him, especially when kids starts to exclude me. No one at school and no one at home. No affection and very alone.

When Gaz came out of the bathroom she went for one of my dressers and opened the top drawer. I watched her, unsure of what she was doing until she pulled out a shirt. She put it on and climbed in my bed, setting herself next to me. She didn't curl in to my side or anything of an affectionate manner, but she laid there.

Somehow, that was comforting in itself. Because as long as she was there, I wasn't alone. Not completely.

That night Gaz didn't go back to her room. She stayed in my bed. Taking a pillow, she adjusted herself on her side and laid there facing away from me. It was a little past eight, a little early for her to turn in. Gaz wasn't a night owl but she never turned in quite so early. I myself tended to stay up later in the evening but with Gaz there I had no issue laying about.

I wondered why she was laying down so early but getting up to catch the bus required she wake up early. Getting some extra shut eye didn't seem like such a bad idea. Not complaining that she was in my bed, I turned off the bedside table for her but to my surprise that's not what she wanted.

"Why'd you turn the light off?"

"I thought you were tired..."

"Well I am but I'm not sleeping yet. Its too early."

I rolled to turn the lamp back on but she stopped me.

"It's fine, you don't have to turn it back on. I'll sleep soon probably."

"You sure?"

"Unless you don't want me in here."

"I don't mind, you can stay."

Gaz didn't say anything but I knew she was staying. She pulled the blanket higher on her shoulder, getting comfortable. I settled in to lay facing her back, although I couldn't actually see it in the dark. I could feel her there though, her body heat. I wanted to hold her, to feel someone in my arms, but I knew better than to just hug Gaz. Even with the circumstance.

So to not rock the boat, I left her as she was. We were quiet in the dark and I could hear her breathing. She was calm, like nothing was out of place. That itself should have been concerning but I was grateful for it none the less. For years my sister hardly recognized me as a person, let alone her brother. Her just being there, acting normal was reassuring even if the circumstance was anything but normal.

Xxxxx

"Gaz your alarm is going off in your room."

In my groggy morning state of mind I could hear my sister's alarm clock through the wall. Not used to being awake on a Thursday morning, I rubbed my eyes tiredly. Gaz was sleeping like a rock but cracked her eyes open when I spoke. She looked over to the wall behind the headboard, giving it an annoyed look.

Throwing the sheet off herself she trudged from my bed out of the room. Seconds later the alarm was off. A glance at my own alarm clock showed it was six in the morning. I laid back to fall asleep and then Gaz was back in the room. She got back in the bed and grumbled for me to share the blanket.

"Aren't you going to get ready for school?" I asked, sharing the blanket anyways. "It's a school day."

"You're staying home."

"It's Thursday, I don't have class."

"What's your point?"

Gaz wasn't one to skip school but I wasn't about to scold her. That was Dad's job, even if he wasn't home. That being said I wasn't going to rat on her either. Leaving her be I decided to just go back to sleep.

"You're not going to make me go?" Gaz asked then.

"Nope." I answered her.

She rolled over to face me, not that I could see her cuz I had my eyes closed still.

"You're not going to call Dad either?"

"Nope"

"Why not?"

Being I was lying on my back, I shrugged both my shoulders.

"A day home isn't the worst crime there ever was to be committed. I won't snitch."

"So when the school calls to ask where I am you'll tell them I'm sick?"

"Sure. Why not?"

The moment I should have been given a 'Thank you, there was silence. Not that I cared. Not really, I was too groggy. As I began drifting back in to sleep the phone rang loudly, the shrill sound jostling both Gaz and I.

"I got the alarm clock" she deadpanned, signaling that it was my job to get the phone.

Sighing, rubbing my face, I sat up. The phone hanging in the hallway kept ringing as I approached it. Not knowing who to expect so early in the morning, I took a bracing breath and picked the phone off the receiver.

"Hello?"

"Dib Human!"

"Good Morning, Zim."

The alien sounded frantic and stressed, first thing in the morning. Not that it was unusual. He did his tinkering and work through the night often times up for days at a time. His species didn't need sleep for recovery.

What I assumed to be a early morning declaration of his new plans to contact the armada turned out to be something unexpected. Zim was still in heat, fiercely so. He informed me he would be over promptly, consenting to lab work so long as I assisted him. As he hung up on me, I wondered what I was going to tell Gaz but she was already leaning out of my doorway when I set the phone on the receiver


	6. Chapter 6

"I want you to fuck him harder."

Between creaks and squeaks of my bed moving with my thrusts, Gaz ordered me how to fuck Zim. With just one of my long T-shirts to drape down her body, she had her thin pale legs crossed as she watched on from the head of the bed. Like she a servant to a mistress, I obeyed her blindly. I couldn't help myself.

Underneath me, Zim laid with his stomach to the sheets and his ass raised high past his torso as I thrusted in to him. The alien had shown up just as promised, flustered and desperate for relief. It was Gaz who was in charge of what happened to his body, however, because she was in charge in mine. So, as she wanted, I pressed Zim in to the sheets by the expanse of his back and rocked him in to the mattress with rough, precise thrusts.

Zim clicked pleasurably and gurgled, his hips shaking as I outright used his body under the command of Gaz. The woman herself had brought a hand up to her chest and fondled her breasts through the cloth there. I raised my eyes to watch, wishing I had my glasses on. I knew what she looked like... but I wanted to see her in full clarity.

I became immersed in the slow, confident touch Gaz worked over her chest. Groping and squeezing her breasts sensually as arousal overcame her. Her legs uncrossed and pressed together, shifting and riding the hem of the shirt up past the valley between her thighs. Her wet, bare sex revealed itself and I could see just how worked up she was already. I near salivated at the memory of gelatinous, yellow eggs having been buried there.

Gaz spread her legs out just then, stretching the hem of the large shirt out with her bent knees. Pale fingers went down between her legs, touching the glossy pearl caught in the overhanging fluorescent lights of my bedroom. I groaned involuntarily at the display, grinding my hips in to Zim as Gaz began tracing circles over herself. Buried to the hilt inside Zim, his body squeezed rhythmically around me. His body trying to milk me of my seed. I used it, attention glued to Gaz.

She took off the oversized shirt, letting it fall wherever it may on the floor. Straightening her back along the headboard she reached up and held the top of it with one hand and let the other work between her legs shamelessly. Her eyes shut slightly as she cussed under her breath, watching as I sunk my length in to Zim repeatedly.

"Mmm...fuck..." Gaz groaned to herself, caving to the stimulation of her own fingers. "A-Ah..."

Tongue darting out to wet my lips, the biggest urge to lick her cunt overcame me. I wanted to try it again, see if I could make her moan for me like that. She knew I wanted to lick her too, she saw it written all over my face.

I'd watched her so openly and focused. But, to both my dismay and joy, I was already busy with one task. There was no way Zim would have been able to handle it if I took a break before he was satiated. Once he was in heat that was it. He needed relief before all else. I couldn't risk it.

"I don't like being second in line but I'll make an exception for Zim here." Gaz told me, breathing heavily as she touched herself with firmer strokes. "I want to see him cum, anyways... but you need to fuck me afterwards. Don't cum in him."

Two long, green three fingered hand reached up the bed and grasped the sheets by Gaz's feet with fierce grip. Zim's spine began curling up. His clicking turned vicious. I had a split second to react, snatching him by the throat before he could lunge at my sister.

"His seed is mine! His seed is mine!"

Holding Zim securely by the throat, squeezed to constrict his air way. I hoped it would calm him down and it did. Or so I thought. He had relaxed for a moment as I continued moving in him, shoving him back down to the bed. Gaz relaxed again.

When he feet came near Zim again, he flared. His chest expanded with a strong inhale, his limbs tensing. There was a swift slash and Gaz pulled her feet in as Zim tried to reach out and claw her flesh. He missed her by a hair, having been clearly aiming to draw blood. My sister had almost lost a foot.

The pleasantly erotic atmosphere disappeared as Zim actually became a threat. He growled and screeched, adamant to get Gaz. Again, he tried to get her. In my ears I could hear my heartbeat racing, blood pumping quickly in fear. I needed to get my sister out but I couldn't let go of Zim.

"Get out and shut the door right away." I told her urgently. "Gaz, go. Get in the shower and wash my scent off of you right away."

"What's wrong with him? Why does he keep doing that?"

"You need to get out right now. I need to-"

Zim tried pulling from my grip and I used my body weight to pin him, moving quickly. Focused on keeping him contained I couldn't look up at my sister. I was terrified for her safety. Zim buckled from underneath me and I feared he'd throw me off of him.

"Out! Gaz, get out!"

Getting off the bed, I restrained Zim as he tried to follow my sister off the bed. Her petite body zipped past us and she left, her bedroom door shutting and closing. Zim seethed, his growling still pissed and territorial. As he looked over his shoulder I could see how his large, red eyes had darkened. He was in primal state.

Now the question was, why?"

Zim became aggressive, fighting my hold on him. I thought he was going to go look for Gaz but he was moving against me instead. To my relief I heard her shower go on. If he did somehow go after her and I couldn't catch him in time he'd probably lose interest if he couldn't smell me on her. If he was in primal state, I hypothesized that he was after her in means of violated territory.

"She's gone." I assured him. "Don't worry about her. Worry about me."

A dry hiss left Zim's mouth. He curled his lips the sharp, jagged points of his teeth. After accepting Gaz was no longer a threat, he returned focus to our copulation. With more vigor than I'd ever seen from him, he began moving powerfully. He rocked his rear in to me roughly, eliciting sharp, choppy gasps as he took it upon himself to work my cock around inside him.

"Zim, take it easy." I urged him, wincing with the firm pounds of his rear o my pelvis. 'That hurt a little-"

"Seed! I need seed!"

The condom slipped as he clenched so tightly around me, snagging it and dragging it down. I tried fixing it, but Zim moved quickly. I couldn't reach between our bodies to fix it. His insides pulsed around me in such a way I'd never felt before. It was like he knew what would draw my seed from me the most effectively. Like he'd memorized my rhythm.

Before I knew it, he was pulling my seed from me and he quivered. His entrance twitched and coiled with the rise of his own peak. I began pulling out quickly but Zim's entrance clamped down on the tip of the condom before I was completely pulled out. In the flash of an eye, Zim's entrance sucked it in and sealed itself shut.

Xxxxx

"The condom... he absorbed it?"

With my underwear on and nothing else I stood inside Gaz's bedroom. She was showered and redressed in fresh pajamas. Meanwhile Zim was in my room, sitting on my bed with his normal red eyes blinking slowly and looking around how he always did. Except, to my horror, he had acquired a sample of my semen and it was sitting in his body.

"He's never done it before. He's acting crazy during sex. I think his heat is getting worse."

"What are you going to do about it? Can't you fix him before he gets any worse? Today he was worse than last time."

"I don't know how! Fuck..."

I clenched at my hair anxiously, beginning to pace. Gaz had the question in mind that I had. She brought it up with a weary glance to the wall separating her room from mine.

"He can't get pregnant from human semen, can he?"

"See, that's the thing. I don't know. I have suspicions that it's possible... in a petri dish his gametes reacted with mine months back and they created a fertile zygote."

"...English Dib."

"My sperm was able to fertilize his egg when done outside his body."

Gaz nodded, but skeptically.

"So, yes?"

"It's not for certain. In other species it's been found that lab-created embryos of hybrids could be implanted and be brought to full term in some cases. But, many of these did not make it past birth. Past birth they were not viable and died." I explained to her. "See, these were animals that would not choose to mate with one another, even breeds of animals who belonged to the same family."

"What does that mean for Zim, then?"

Sighing heavily, I kept pacing.

"If two species do not mate on their own and create non-viable off spring when forced, it is implied they should not breed. Zim is an advance creature and although he hadn't initially chosen to mate with me, he did make the conscious choice to consent to it although with contraception." I explained to Gaz. "If he's grown to craving seed and exhibiting territorial behavior with me, as well as his gametes reacting with mine, he must know something I don't. Even if just instinctually."

"If you're so worried about creating a baby, why did you try it on your own in the first place you dumb ass? Kind of contradicting, Dib."

"It was for research, I hadn't intended to bring it to term if it lived. The embryo died but I always suspected it was from lack of proper incubation. I don't have the technology to mimic Zim's biology. He's an advanced species."

Slowly it was catching up with Gaz. She nodded a few times with face passive. It clicked.

"And you don't have the technology to abort it if it grows."

"Exactly." I confirmed. "I don't know what to expect from this. This could be a breakthrough in science or a complete disaster. Zim is unstable. I needed to fix him, not impregnate him."

"...Here's a thought. What if impregnating him is the way to fix him?"

I stopped my erratic pacing, freezing on the spot. I thought over Gaz's comment and blinked. I blinked quite a bit as the gears in my head began turning furiously. Gaz leaned back in bed casually and picked up her T.V remote, flicking the T.V on casually. She then pointed the remote at me.

"I never saw the impregnation testing in your logs but from what I have seen it seems like Zim's problem has been a craved pregnancy. His heat... your seed. It's what he wants. Maybe some crazy shit is happening to him in the midst of all that adrenaline and mating, but his body must know what it wants." She suggested. " Maybe if he has a baby it'll reboot his body. I'm not a scientist. I don't know. It just seems possible. If you can't reverse, maybe you can actually douse it out. "

I was floored because Gaz conjured a valid theory. If what she said was in fact true, I would have Zim back to his original biology, endocrine system restored. But, a successful pregnancy didn't come without consequence...

xxxxx


	7. Chapter 7

It was an interesting period of observation to say the least. Zim didn't like it, but I was running tests on him daily. My first concern was his hormones. I'd tested desperately, days gone in what felt like the blink of an eye. Zim's original dysfunction of his endocrine system was now almost overshadowed by another problem completely, or rather a worry of another problem.

I was trying to decipher whether he was pregnant or not, but the results were inconclusive. He'd had hormone fluctuations before, dramatically so. His tests spiked and dipped all the time so I couldn't determine whether the ones he was having now were an effect of a potential pregnancy, or simply worsening due to the prolonged nature of his endocrine system dysfunction.

If I wasn't doing college homework, I was at my own personal desk rifling through data. It felt like I hadn't had a proper night's sleep in months despite having been only been investigating Zim's current state for about a couple of weeks. I was exhausted and could barely care for myself. Meanwhile, I was now responsible for both Zim and Gaz's safety tenfold on top of my own body. Feeling my body begin to give out on me as I stared blankly at my computer screen, I banged head down on my desk, a heap of random sheets scattering. How was I going to take care of everything? I couldn't bring myself to care that moment.

"Dib, it's dinner time."

My sister walking up to my door drew me from the powernap I intended to take. I didn't lift my head as she spoke to me, but she knew I was listening.

"Give me a few minutes. I'll get something made."

"I'm not that hungry, anyways. I was going to make some ramen." She responded, declining my offer to make dinner. "Do you want one?"

"I'll take a ramen, yeah. Shrimp, please."

My sister's socked feet scuffed along the floor as she went to get the ramen made. It wasn't much of a meal but honestly, I was just glad I'd get something to shovel in my mouth. Eating and going to bed sounded good because I had classes the next day. I was missing out on a lot of rest, but it wasn't an excuse to fall behind in my classes. Dad wasn't around much at all to care about anything, but the last thing he'd want is to find out I'd fallen behind in my studies. He couldn't have cared less if I was an adult or not, let alone alive, he just wouldn't have stood for bad grades.

Gaz moved around the kitchen down stairs as I contemplated my plans for the night. After a few minutes of tiredly contemplating my choices, I stood up from my desk and trudged to the shower. With a towel around my waist, I was toweling off my wet hair when Gaz called me down.

"Alright. Give me a sec."

Pajama bottoms on, I went to meet her at the dining table. She was rummaging through the fridge for her hot sauce when I arrived. It was quiet as we ate, just our utensils clicking the ceramic bowls. Gaz raised her eyes from her food to stare at me, chewing slowly.

"Holy shit, you look tired." She commented simply. "You need to sleep."

"I wish I could. I can't seem to stay asleep more than a few hours before I wake up. I'm doing math equations and hypothesizing in my sleep, it never ends."

My sister kept eating, tapping her nails along the table top. The polish of choice today was a navy blue of sorts, I noted. It was freshly painted, unlike how her nails usually were with chips and whatnot.

"Your nails look nice." I told her, catching her attention. "That's a nice manicure."

"You know about manicures?"

"Well no, but your nails look nice. Usually they're all chipped. You don't pay much attention to them."

"The cosmetology girls needed practice. One of my classmates recruited me during recess."

"Oh. Nice."

The idle talk didn't get far, but it was so surreal to be able to talk to my sister on such casual terms. She hadn't lost her intimidating front, that was who she naturally was. But, she was noticeably more approachable. It was enough that I could look her in the eye daily. And when I looked her in the eye just then, she seemed to be thinking the same thing I was.

"...You think this shit with Zim is going to play out alright?"

I didn't have an answer for her. Nor did I want to pretend like I had any clue.

"I wish I knew, Gaz."

"You know him. You'll figure it out."

"And if I can't?"

Gaz brought some noodles to her mouth and chewed as if we weren't discussing a potential catastrophe.

"You'll figure it out. You always do."

Xxxxx

"Dib!"

I was being struck upside the head with a text book, waking up to the judgmental eyes of my professor and peers. My professor was annoyed with me. I didn't blame him.

"S-Sorry professor..."

"You're dismissed, Dib. Go home and get some rest if you're so tired."

"I can-"

"Go. Home."

Packing up my bag I left the room. The lecture carried on as I entered the hallway, my stomach knotted in regret. It was an awful ride home that afternoon. As I passed the high school I briefly thought of Gaz. What I would have given to just to have her home when I got there. Have her take care of me...

With every intent to nap when I got home, I was struck alarmed at the sight of front window broken open. There was blood smeared along the glass shard. My first thought was a burglar, but upon closer inspection of the window, the blood wasn't the red that came from humans. It was thick, almost magenta in color.

"Zim?"

Entering my own home carefully, I called out for the alien. There was no answer. I tried again, creeping through the kitchen and listening for any sign of him. There was blood streaking along the floors, so I followed it. The trail led up the stairs and in to my bedroom.

"Hello? Zim? You okay?"

My room was empty, the bathroom door left ajar. At a distance I could hear the skittering, almost like claws tapping porcelain. Pushing open the door slowly, I peeked my head in. And there he was, sitting in the tub. The once stark white material of the tub was now streaked and bloody. The cuts on Zim's arms and body were superficial though, nothing horrendous. The blood was coming from between his legs.

"Dib, human..."

Zim's voice was low and hoarse, his usual green skin having dulled to a sickly off-white color. The pigment in his eyes turned almost grey, the color muddled with a red hue. He was breathing heavily, limbs lethargic as I hurried over to him.

"What happened? Zim-"

Weakly lifting a clawed hand, he took me by the shirt.

"Get it out..." He pleaded. "Get it out of Zim."

Lack of sleep led me to believe my ears were playing games with me.

"G-Get it out?"

"Get it out!"

Suddenly, Zim's head was thrashing and he wailed. His stomach visibly moved. The flat, smooth surface of his abdomen rippling as if something moved from within him. The muscles clenched and more blood seeped from between Zim's legs. He screamed again and I realized he was having contractions. The alien in my tub, whose biology was to lay eggs, was having a live birth.

I had impregnated him...and whatever hybrid we'd created was on its way.

"Oh, fuck."

The screaming continued, and I knew something was wrong. There was no reason for him to bleed like that, at least not from what I gathered from his specie's breeding process. He was just to supposed to lay fertilized eggs. They would hatch outside the body...

Time wasn't on my side that day. I leapt in the tub with Zim and placed my hands on his abdomen, feeling whatever offspring was inside of him move around. His legs were shaking, more blood coming out of him. This time, it was lighter. Waterier. Reaching down to his entrance, I prodded carefully. As I suspected, I could feel the head of something coming out of him.

"I guess you were pregnant." I announced, as if Zim couldn't gather that for himself. "I'm so sorry. You're gonna need to push if you want it out. Come on, push."

There was no way to tell what exactly was going to come out of Zim. But, there was no other choice but to face it bravely. Hopefully, the blood loss wasn't killing Zim. If it was, I wouldn't have enough time to intervene. Either I got it out of him now, or that was it.

I feared with every fiber in my body that the neighbors could hear Zim's commotion. He did as I instructed and pushed with his abdominal muscles. When the head popped out, I was surprised to not only see antitea, but tufts of black hair. The skin was green, but lighter than Zim's natural complexion. The baby's eyes were shut as the rest of her body slid out, body covered in a mixture of Zim's blood and birthing fluids.

He gave a huge breath of relief once the baby was out. He was frail, and he looked like someone had completely sucked the life out of him... but he was stable. Looking down at the infant freshly born, I couldn't believe what I was seeing. At first glance, it looked almost human.

She looked almost human.

"It's a girl, Zim." I said in awe. "An actual, Girl."

Her nose was very small...and her eyes were large. The general shape of her face reminded me of Gaz if anything. The off-green shade of her skin didn't so much make her look like an alien as it did maybe a sickly child...had she not had antennae you wouldn't know. At least, that's what I thought before taking a look at her hands.

Unlike Zim, she had five fingers on each hand and five toes on each foot. But, her nails were claws just as his were. I touched one carefully, recoiling back as it sliced open the tip of my fingers. She began to cry, revealing a mouth full of tiny, pointy teeth. It was then that her eyes opened for the first time.

She had red eyes. Solid red eyes with no pupil. Taking a nearby towel, I wrapped the baby up and set her aside. She cried but my attention was on Zim. He stared at the bathroom wall blankly, not caring for the sound of the baby at all. He didn't react, he didn't move.

"Do you need anything?" I asked him.

"Zim would like to rest."

In a tub completely soiled in his own bodily fluids, Zim shut his eyes and fell asleep. Looking at the baby, I realized his bleeding probably came from her claw-like nails tearing his insides. Zim seemed comfortable enough now that I surmised he didn't any further medical treatment, he was just exhausted like any other person who gave birth.

The baby still cried. I still couldn't believe I was holding a baby... let alone wrap my head around the fact that she was mine. Zim and I had created a half breed... likely the only one of its kind to ever exist. What did that mean for us down the line?

Zim hadn't stirred from his sleep for hours. I spent the time cleaning, sleep deprived and listening as the baby cried. I couldn't soothe her, so I left her until she tired herself out and fell asleep like Zim. By the time I had all the blood cleaned up from Zim's break in and dash to my bathroom, all that was left was to clean the tub he actually laid in.

Thankful to have a detachable showerhead, I turned the water on and began gently spraying Zim. His eyes blinked open as I cleaned him off, spraying the blood off of him and the tub walls. As if he hadn't been in agony hours prior, he stood up and stepped out of the tub.

"Where are you going?"

"Zim is going home."

"But Zim-"

Confidently, Zim strode on past me. He completely ignored the baby.

xxxxx


End file.
